Biography: San Giacomo was born in New Jersey and attended Washington College and the Carnegie Mellon School of Drama. She has appeared in the films Sex, Lies, and Videotape (1989), Pretty Woman (1990), Quigley Down Under (1990), and Nina Takes a Lover (1994), among others. She was the lead character in the sitcom Just Shoot Me (1997-2003) and did voice work for the animated series Gargoyles. She was to have made her return to television on The WB's new drama Related in 2005, but the character she was to play was recast due to creative differences. She also appeared in the Stephen King TV miniseries The Stand, playing the part of Nadine Cross.

San Giacomo has been married twice; to actor Cameron Dye (1990-1998), with whom she has a son, Mason (born 1996), and to actor Matt Adler (since 2000). She is the cousin of Torry Castellano, a member of the rock group The Donnas.